Abstract

Carboxymethyl chitosan (CMC) was tested as corrosion inhibitor for mild steel in peat water using weight loss methods. The result showed that the inhibition influenced by the peat water pH, contact time and CMC concentration, which the inhibition at optimum on pH 7 and contact time 3 days i.e., 93,66%. The inhibition efficiency of this inhibitor increases with increasing in the CMC concentration. The inhibition action of CMC on the steel surface obeys modified Langmuir isotherm and assumed to occur via chemisorption on the metal surface with value Goads -35,413 kJ mol-1 . The negative value Goads of indicates that the CMC inhibitor is spontaneously adsorbed onto mild steel surface. The inhibition efficiency is also characterized bases of activation energies of corrosion reaction in the absence and with presence of CMC and the formation of passive film on the surface metal studies the using Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX).
Keyword: Carboxymethyl chitosan, Corrosion inhibitor, mild steel, peat water